Brief overview
- Prognosis: Very dependent on the underlying cause. If this is treatable, the prognosis is good. If the precipitating condition is not treatable, the prognosis is usually poor and life expectancy may be reduced.
- Causes: For example, diseases of the organs (such as liver or heart), inflammation of the abdomen (for example, peritonitis), infections such as tuberculosis or chlamydia, cancer (including stomach or colon cancer), injury to abdominal organs, protein deficiency (such as from malnutrition, kidney disease, or cancer)
- Therapy: treatment of the underlying disease. In cases of severe ascites, removal of the fluid from the abdomen by paracentesis. Placement of a permanent catheter in case of repeated ascites.
- When to see a doctor? At any suspicion of ascites! If left untreated, it can develop into a life-threatening condition in the worst case.
Ascites: Definition
The term ascites stands for abdominal dropsy. This is a pathological accumulation of fluid in the free abdominal cavity.
The human body consists mainly of fluid. It is distributed among the cells, the environment between the cells (interstitium) and the blood vessels. Just under two-thirds (about 30 liters) of the fluid is in the cells themselves, just under one-third (about ten liters) is between the cells, and about three liters of pure fluid is in the blood vessels.
The blood vessels are sealed by cells and are partially permeable to fluids. This is particularly the case at the smallest vessels, the capillaries. When the heart pumps blood through the body, the pressure in the blood vessels increases.
This also causes some fluid to enter the surrounding tissue – similar to a garden hose with tiny holes: The higher the pressure, the more water is lost through the holes.
From there, the fluid is normally transported via the lymphatic channels back into the veins and thus into the bloodstream – the outflow of fluid from the vessels and the return transport are normally in equilibrium.
As long as this balance is intact, there is always a roughly constant, minimal amount of fluid in the abdominal cavity in healthy people. It acts there as a kind of lubricant between the organs.
If the balance is disturbed, fluid may leak out of the vessels or no longer be transferred back into the vessels at the normal rate: Fluid builds up in the tissues (edema). If this happens in the abdomen, it is called ascites.
Ascites: Symptoms
The typical symptoms of ascites are a greatly increased abdominal girth, accompanied by a feeling of pressure and weight gain. If a lot of fluid accumulates in the abdominal cavity, it presses against the surrounding organs.
This sometimes results in pain and bloating. Depending on the amount of fluid, the abdomen may still be soft in early stages. In advanced stages, however, it usually becomes hard.
In addition, in some cases an umbilical hernia develops. In this case, a small part of the internal organs (mostly fat) pushes through the weakened abdominal wall at the level of the belly button. A soft circumferential proliferation forms above the belly button.
If parts of the intestine or other abdominal organs are pushed through the opening in the abdominal wall, their blood supply may be restricted. This is an emergency that requires urgent medical attention. Indeed, if the blood supply is impaired for a prolonged period of time, there is a risk that parts of these organs will die.
Life expectancy with ascites
The accumulation of fluid in the abdominal cavity is not life-threatening in itself, as long as no vital organs are impaired in their function by the additional pressure.
If the cause of ascites can be completely eliminated (for example, in the case of a nutritional albumin deficiency), life expectancy is usually largely normal.
If a complete cure is not possible (for example, through a successful liver transplant in the case of liver cirrhosis), this often has a negative effect on life expectancy. In the worst case, only a few weeks or months pass between the diagnosis of ascites and death, but usually several years.
Ascites: Causes
Various mechanisms may disturb the fluid balance and thus cause ascites:
- Increased pressure within the blood vessels, forcing more fluid out (such as in portal hypertension or right heart weakness).
- Increased permeability of the cell walls (such as in the case of inflammation)
- Disturbances in lymphatic drainage (in the case of obstructions caused by tumors or scarring)
- Protein deficiency (for example as a result of hunger – visible sign is the “water belly”)
These mechanisms sometimes occur alone, but sometimes in combination.
About 80 percent of all ascites cases are due to severe liver damage such as cirrhosis. In other cases, tumor diseases, inflammations or disorders of the lymphatic drainage are the triggers of ascites.
The kidney then excretes less urine, leaving more fluid in the body. It also releases hormones that drive blood pressure up again. The increased pressure and fluid in turn cause even more fluid to leak from the vessels into the surrounding tissues.
Below is an overview of the most common forms and causes of ascites:
Portal ascites
The portal vein(portal vein) brings nutrient-rich blood from the abdominal organs (such as the stomach or small intestine) to the liver, which functions as a key metabolic and detoxification organ. If blood flow in or around the liver is obstructed, blood pressure in the portal vein increases, resulting in portal hypertension (also called portal hypertension or portal hypertension).
The increased pressure causes more fluid to leak out of the vessels into the surrounding area, resulting in what is known as “portal ascites.” This is by far the most common form of abdominal dropsy. From the point of view of the blood circulation, the cause lies before the liver (prehepatic), in the liver (intrahepatic) or after the liver (posthepatic):
Prehepatic
These blood clots often result from inflammation of the pancreas or a tumor.
Intrahepatic
The most common cause of portal hypertension (70 to 80 percent) is congestion in the vein due to causes within the liver (intrahepatic).
Normally, nutrient-rich blood from the digestive organs enters the liver tissue via the portal vein, where it is distributed and cleansed of harmful substances such as toxic metabolic waste products. In addition, many nutrients are stored in the liver.
When inflammation of the liver is prolonged, destruction and regeneration of liver tissue results in connective tissue remodeling of the organ. The liver becomes small and hard. The poorly perfused connective tissue obstructs the blood flow in the portal vein, and the pressure increases. The final stage of such connective tissue remodeling is called liver cirrhosis.
Possible causes of such inflammation are drugs (for example, non-steroidal anti-inflammatory drugs = NSAIDs), autoimmune reactions, viral infections (for example, hepatitis B or C), nutritional or metabolic (as caused by Wilson’s disease).
Fatty liver usually regenerates completely in early stages (before extensive connective tissue remodeling has begun) after the cause is abolished.
Posthepatic
If the blood flow from the liver to the heart is disturbed (posthepatic), the pressure in the portal vein also increases.
One possible cause is drainage disorders of the hepatic veins (Budd-Chiari syndrome), for example due to thrombosis, tumors or infections. Symptoms include ascites, a congested liver, pain in the upper abdomen, nausea and vomiting.
If the blockage of the veins draining blood from the liver persists (chronic), this too may lead to cirrhosis.
In rare cases, disease of the heart and associated outflow obstruction are the cause of ascites (cardiac ascites):
Normally, blood from the liver enters the right ventricle of the heart and from there is directed via the lungs to the left ventricle (“pulmonary circulation” or “small circulation”). From there, the acidic and nutrient-rich blood is pumped to the organs (“systemic circulation” or “large circulation”).
The blood backs up into the liver. There, the pressure rises and disturbs its function. Under certain circumstances, jaundice (icterus), blood clotting disorders and ascites may develop.
Right heart failure often arises from weakness of the left ventricle (see article Heart failure). Diseases of the lungs are also the cause in some cases.
Another possible cause of cardiac ascites is the so-called armored heart: in this case, the pericardium has become so thickened and hardened due to repeated inflammation (chronic pericarditis) that the heart muscle inside it no longer has enough room to expand accordingly when filled with blood.
As a result, blood backs up in front of the heart. As a result, fluid collections develop in the ankles and lower legs (edema) and in the abdomen (ascites).
Malignant ascites
Malignant ascites refers to abdominal dropsy caused by cancer: Malignant tumors here constrict the lymph vessels in the abdomen. These then take up less fluid from the abdomen and transport correspondingly less of it away – ascites develops.
Most frequently, people with cancer of the peritoneum (peritoneal carcinomatosis) develop malignant ascites. The cancer cells that settle on the peritoneum usually originate from tumor sites on neighboring abdominal organs, mainly the stomach, intestines, ovaries or pancreas.
In some cases, cancer of the liver (liver carcinoma)causes malignant ascites. In some cases, metastases from cancers of other organs such as the intestine, lung, breast, stomach or esophagus also cause malignant ascites.
Inflammatory ascites
Inflammation causes the release of messenger substances that increase the permeability of the vessel walls.
In this form of ascites, the fluid that accumulates in the abdomen is cloudy, and bacteria or other pathogens may be detected in it. Possible causes of inflammatory ascites include:
- Acute pancreatitis: Inflammation of the pancreas is manifested by severe, belt-like upper abdominal pain, fever, nausea and vomiting. In some cases, jaundice (icterus) and abdominal dropsy develop later.
- Tuberculosis: Although tuberculosis is no longer particularly common in Germany, it is still very widespread in many parts of the world. If the symptoms show mainly in the abdomen (abdominal tuberculosis), they may lead to abdominal pain, fever, weight loss, diarrhea, and in some cases ascites.
- Inflammatory vascular disease (vasculitis): inflammation of vessels in the abdomen may cause ascites.
- Sexually transmitted infections (genital infections) may rise from the sexual organs into the abdomen. They then lead in some cases to peritonitis and thus possibly also to ascites. Examples include infections caused by chlamydia or gonococcus (gonorrhea).
Hemorrhagic ascites
Chylous ascites
Chylous ascites is leaked lymphatic fluid. The accumulated fluid in the abdominal cavity is milky. The obstruction of the lymphatic drainage is mainly caused by tumors, their metastases and in some cases by scarring after abdominal surgery.
Other causes of ascites
Among the rare causes of ascites is a severe albumin deficiency (hypalbuminemia). Albumin is an important transport protein in the blood. Due to its concentration inside the vessels, it increases the so-called colloidosmotic pressure there, which keeps the fluid in the vessels.
If too little albumin is present, this pressure drops. As a result, more fluid escapes from the vessels into the surrounding tissue and is no longer reabsorbed to the same extent via the lymphatic vessels. This results in water retention in the tissue (edema) and, under certain circumstances, ascites.
The causes of albumin deficiency are manifold:
- Hunger, malnutrition, anorexia nervosa: The images of emaciated children with water bellies in impoverished regions are particularly well known here.
- Exudative gastroenteropathy: Increased protein is lost via gastric and intestinal mucosa or lymphatic vessels, resulting in a decrease in the protein level in the blood. Typical symptoms are severe diarrhea, edema, ascites, and weight loss. Triggers of exudative gastroenteropathy are, for example, Crohn’s disease, ulcerative colitis or celiac disease.
Another, albeit rare, cause of ascites is in the gallbladder area (biliary ascites). For example, in some cases of gallbladder inflammation, a perforation of the gallbladder wall occurs. Bile and pus then empty into the abdominal cavity.
Other rare causes of ascites include hypothyroidism(hypothyroidism) and Whipple’s disease (rare bacterial infectious disease).
Ascites: Therapy
The treatment of ascites aims to relieve acute symptoms caused by fluid accumulation. Most importantly, it is important to find and treat the underlying cause.
Treatment by the physician
If the accumulation of fluid in the abdominal cavity causes serious symptoms such as severe pain or shortness of breath, the physician has the option of removing the fluid in the abdominal cavity by means of a minor surgical procedure (paracentesis).
In this procedure, the doctor pierces the abdominal wall with a hollow needle under ultrasound guidance and sucks out the excess fluid. This helps the patient to get rid of the watery belly quickly. However, the procedure carries a (small) risk of infection and bleeding.
If ascites recurs, it is often necessary to repeat the treatment. Then an indwelling catheter may help.
However, the actual treatment depends on the underlying disease:
Liver
If increased pressure in the portal vein is the cause of ascites, the following measures may be considered, depending on the cause:
Disturbances of blood flow before or after the liver, often have blood clots or tumors as the cause. Blood clots, depending on their size and location, are treated with appropriate medications (for example, “blood thinners” for thrombosis) or surgery. In the case of tumors, chemotherapy or radiation therapy are also used.
Inflammation of the liver caused by viruses (for example, hepatitis B or C) can be treated well in many cases with antiviral drugs.
If the inflammation is caused by taking medication (for example, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or acetylsalicylic acid (ASA)), the drug is replaced, if possible, by other drugs that are less harmful to the liver.
In autoimmune diseases that lead to ascites, treatment is usually with drugs that suppress the immune system (immunosuppressants), for example cortisone.
Metabolic disorders such as diabetes mellitus or Wilson’s disease are treated with drugs according to their clinical picture.
The liver is a very regenerative organ that recovers well from many types of damage. However, if connective tissue remodeling of the liver is far advanced, it ends in cirrhosis of the liver, which is not curable.
Normally, blood flows from the portal vein through the liver tissue, is pooled behind the liver in the hepatic veins, and is further directed toward the heart. In the case of cirrhosis of the liver, however, the blood flow through the liver tissue is disturbed.
Under certain circumstances, surgery may be required to create a connection between the portal vein and the hepatic vein, a so-called “transjugular intrahepatic portosystemic shunt” (TIPS).
The diverted blood flow bypasses the liver. The blood does not back up to the same extent in the portal vein because it flows out unhindered – the pressure in the portal vein and thus the risk of ascites decrease. This operation is recommended if ascites repeatedly forms.
In this way, repeated paracenteses can be avoided and the quality of life can be improved.
Curing cirrhosis of the liver and thus ensuring a normal life expectancy is only possible by transplanting a donor liver (liver transplantation).
Heart
In the case of fluid retention due to a heart problem, the following options can be considered:
In the case of heart failure, an attempt is made to maintain quality of life and prevent progression of the disease with medications (primarily blood pressure-lowering or dehydrating (diuretic) classes of agents). Depending on the severity and cause of the disease, heart transplantation may also be considered.
Many drugs for heart disease have a negative effect on the liver. If both organs are affected, the doctor will carefully consider which medication is best for the patient.
In the case of an “armored heart,” treatment depends on the cause. For example, antibiotics may help if the infection is caused by bacteria, and anti-inflammatories, dialysis or immunosuppressants for autoimmune diseases may also help if necessary. In severe cases, fluid from the pericardium or the entire pericardium is removed.
Other causes
Inflammatory diseases that lead to ascites are also treated according to their cause. Antibiotics and anti-inflammatory drugs may be considered.
Bleeding from an injury can often be stopped by surgery.
In many cases, a high-protein diet compensates for a nutritional albumin deficiency.
Increased protein loss due to chronic gastrointestinal disease can also often be compensated for by increased protein intake. In addition, these inflammatory diseases are often treatable with medication. As a result, less protein is lost through the gastrointestinal mucosa.
If there is an underlying kidney disease, the focus is on treating the cause (for example, medication for high blood pressure). If complete kidney function is irretrievably lost, only transplantation of a healthy kidney will help.
In the case of ascites caused by an albumin deficiency, blood transfusions or infusion solutions containing albumin are used in an emergency. These help keep fluid in the vessels and improve their reabsorption via the lymphatic system.
What you can do yourself against ascites
- Low table salt: Avoid too much table salt if you have ascites, because the sodium it contains promotes water retention in the body. Ask your doctor about the best amount to limit your daily salt intake to.
- No alcohol: Liver diseases such as cirrhosis are the most common cause of ascites. To avoid putting additional strain on the diseased organ, it is recommended that you avoid alcohol at all costs.
- Light whole foods: A light whole foods diet is generally recommended for liver disease, i.e. a whole foods diet that avoids foods that are individually intolerant or difficult to digest (for example, fried or high-fat foods and legumes).
- Bed rest stimulates the body to excrete more water. This is because blood is distributed differently when the patient is lying down than when he or she is standing, and the vessels in the abdominal cavity are also more bulging – a signal for the kidneys to excrete more fluid. Under certain circumstances, this helps to eliminate ascites.
Ascites: When to see a doctor?
Another possible explanation for an enlarged abdomen is rapid, unwanted weight gain due to hypothyroidism.
So in otherwise healthy people, an increase in abdominal girth need not immediately be thought of as ascites. Abdominal ascites is much more likely to develop in people who already have serious pre-existing conditions, for example of the heart or liver.
Ascites is also rarely the first symptom in cancer, and usually numerous other complaints have already occurred beforehand.
Nevertheless, if you suspect an accumulation of fluid in the abdomen, it is always advisable to consult a doctor! Abdominal dropsy is usually the symptom of a serious illness or injury. In addition, if left untreated, it can lead to life-threatening peritonitis or acute respiratory distress.
Examination of ascites
When a certain amount of fluid is present in the abdominal cavity, ascites can usually be recognized at first glance by the enlarged abdominal circumference. The physician takes further important information from the patient’s medical history (anamnesis).
During the subsequent physical examination, the doctor palpates and taps the abdomen. If there are wave-like movements under the abdominal wall, this indicates a larger edema.
By means of ultrasound (abdominal sonography), the doctor can detect even the smallest accumulations of fluid of 50 to 100 milliliters. In addition, the liver, heart and digestive organs can also be examined for the causes of ascites.
A blood test is also one of the standard examinations for ascites: In some cases, changes in the blood count indicate liver or heart dysfunction, which can be a possible cause of ascites.
The exact form of ascites can be determined with a puncture: In this procedure, the physician punctures the abdominal cavity with a thin hollow needle through the abdominal wall and takes a sample of the accumulated fluid. The color of the fluid alone provides important information about the cause of the ascites.
Frequently asked questions
You can find the answers to the most frequently asked questions in our article Frequently asked questions about Azites.
